Evanna Lynch - J. K. Rowling wrote Luna Lovegood to be more like this lovely lady right here. :)
Evanna Lynch, who plays Luna Lovegood in Harry Potter, once wrote to J.K. Rowling begging for at least a tiny role in one of the films. At the time she was young and was dying due to her anorexia. She mentioned it to J.K. and begged to have one part in the film before it was too late. J.K. Rowling responded with a deal: she’d give her a part if she got better. Evanna got better and never returned to her anorexia.